Condensation chloromethyl benzoates



Patented Sept. 30, 1952 T UNITED STATES, PATENT.

. CON-DENSATION CHLOROMETHYL BENZOATES Robert A. Heimsch and William S.Emersom: I Dayton, Ohio, assignors to -Monsanto Chemical V Company, St.Louis, Mo., a corporationof-Dela Ware NoDrawings ;Application March 2519 50,

, Serial No. 151,992

The present invention relates to esters of diaryl dicarboxylicacids anddeals more particularly with the production of certain esters of1,2-bis- (carboxyphenyl) ethane. The invention provides roams; (Cl.zen-r15 an improvedmethod for-the preparation of suchf 5 esters."-

"Esters" of 1,2 highly valuable 'asplasticizers and as intermedibis(carboxyphenyl) ethane are ates for th'e-production-of surface-activeagents, 1

Water repellants, lubricants, etc. While a'number of these esters havebeen known for some time, their usefulness hasbeen limited because theknown methods'of preparation either gave very poor yields or werebasedon the use of difiicultly available starting materials.

,Now wehave found that esterslof l,2-'bis(car boxyph'e'nyl) ethanewithaliphatic, saturated a1- cohols of from 1 to 8 carbon atomsarereadily obtainable by heating an. alkyl-(halomethyl) benzoate inaqueous-suspensions of nickel-aluminum alloys, the reaction.proceedingsubstantiallyV according to the scheme:...

y is contacted with'the.--.a1loy; Optimumrryieldszof';

the ester are obtained by conducting:- the-;hejat ing for a time-oisay,--;one-hour to twentysfourhours. i c

It has been found that during a the: reaction; some of the" alkyl(halomethyl)benzoater-is ia1so:- converted ruby-products; i. e.;,toluic:acid-?andtoluates. Separationof "thef desired dicarboxyla-tesfrom the-by-productsds readilyeffected-a because of the wide differencesin-therespective boilingpoint-andsolubility:characteristicsw 360G a t iIn some instances, particularly when'iworking; c I H coon with thehigher'alky1(halomethylibenzoate it:

,2- D G: maybe advantageous; to employan-inertjdiluentc I v r or a polar"solvent-with the aqueous suspension: R000" 3 of the nickel-aluminumalloy. As examples-of:

inlwhich. Ri-is an" alkylcgroup of1from :1 to 8 carbon atoms and Xis'halogen. AlkylKp-halomethyl) :benzoates us'efullfor the present pur-'pose include methyl 4- '(c'h1oromethy1) benzoate, butyl 2-(chloromethyl) benzoate; ethyl 3- (bromo methylibenzoate, isoamyl '4--(iodomethyl)benzoate; 2 ethylhexyl 4- (chlo'romethyl) benzoate,

etc.? As illustrative of esters of 1,2-bis(carboXy-- phenyl) ethaneobtainable by the present process aqueoussuspensionof the nickelaluminum alloy,

at below the decomposition point of the halide, at. say, temperatures offrom 140? C. .to 150 0., depending upon the nature of the individualreactants employed. Conveniently, the heating is conducted by refluxingthe mixture of halide, water and the nickel alloy. Inasmuch as theploy'ed maybe-mentionedl'clioxane benzene; etlrano1,ether, etc.; 1. l

The -.-nickel,aluminum alloy :fcundsuitablefior,- the present processmay containvaryingfamounts 5 of nickel alloyed witlr'a-luminum: Goodresults" are obtainable by using the-alloys-describedz-in? the Raneypatent, U. S. 1,628,190, and ,zconsisting of from 10% to 85% nickeland'from-90.%uto 15% aluminum, and particularly thealloys disclosedtherein which---consist of approximately equal quantities ofnickeland'alumin'um. Silicon may be present.- The alloy generallydisclosed intll. S.

Patent 1,628,190 will be hereinafter referred to briefly as .Raneyalloiyl" The invention is further illustrated, butjnot;

limited by the following exampl es:

Emampiri,

Twelve grams of Raney alloy..(from Gilman %Paint and Varnish Co.) and100 cc. of water The resulting mixture was then refluxed for a washingswere then combined and the benzene was removed by distillation underreduced pressure. The material which remained after separating thebenzene was allowed to cool, and the crystals which formed in the cooledmaterial were filtered off, washed with hexane and then recrystallizedfrom methanol. The crystals thus obtained com rised substantially pure1,2-

bis(4',4" carbomethoxyphenyl) ethane, M. P. 118.5 C.'119.0 C.

Example 2 This example shows the use of an inert solvent with water inthe pre aration of 1,2-bis(4',4"- carbomethoxyphenyl) ethane.

Forty grams of Raney alloy, 150 cc. of dioxane and 150 cc. of water werecharged to a 1-liter flask and the mixture was heated to a temperatureof 80 C. To the mixture there was then added 1' 8 g. (0.965 mol) ofmethyl para(chloromethyDbenzoate during a time of 45 minutes and attemperatures of from 80 C. to 90 C. The resulting reaction mixture wasthen maintained at a temperature of from 87 C. to 91 C. for a time of 4hours. At the end of that time 75.0 cc. of benzene was added to thereaction mixture and the whole was then cooled, with rapid stirring. Theproduct was then filtered to remove the Raney alloy, and the filtratewas allowed to separate into an aqueous phase and an organic layer. Theaqueous layer was washed with benzene. and the washings thus obtained aswell as washings obtained by washing the filtered alloy with benzenewere combined with the separated organic layer. Distillation of thecombined organic layer and benzene washings to remove benzene anddioxane gave as residue a material from which the crude1,2-bis(4',4"-carbomethoxyphenyl)ethane, M. P. 115-1l8 C., crystallizedout upon cooling. Recrystallization of'the crude material, employingmethanol, gave the substan-' tially pure1,2-bis(4',4"-carbomethoxyphenyl) ethane.

Operating as in the above examples, but using ethyl, n-butyl or2-ethylhexyl 4-(chloromethyl) benzoates instead of the methyl ester,there may be similarly obtained 1,2-bis(4',4"-carboethoxyphenyl) ethane,1,2-bis(4',4"-carbo n butoxyphenyDethane or1,2-bis[4',4"-carbo-(2-ethylhexyl) oxyphenyllethane.

We claim:

1. A process for producing a dicarboxylate having the general structure:

ROOC COOR wherein R is an alkyl group of-from 1 to 8 carbon atoms, whichincludes refluxing a mixture comprising Raney .alloy, water and anlesterhaving the general structure:

4 2. A process for producing a dicarboxylate having the generalstructure R000 coca wherein R is an alkyl radical of from 1 to 8 carbonatoms, which includes heating a mixture comprising an aqueous suspensionof an alloy, containing from 10% to nickel and from to 15% aluminum, andan ester having the general formula ROOC in which R is an alkylradicalof from 1 to 8 carbon atoms, and recovering said dicarboxylatefrom the reaction product.

3. A process for producing a dicarboxylate having the general structureROOC in which R is an alkyl radical of from 1 to 8 car-- bon atoms,which includes heating at a temper:

ature of from 40 C. to C. a mixture comprising an aqueous suspension ofan alloy, containing from 10% to 85% nickel and from 90% to 15%aluminum, and an ester having the general structure in which R is analkyl radical of from 1 to 8 carbon atoms, and recovering saiddicarboxylatev from the reaction product.

4. A process for producing a condensation product which includesrefluxing a mixture com-' prising Raney alloy, water and methyl4-(chloromethyDbenzoate and recovering 1,2-bis(4',4"

carbomethoxyphenyDethane from the reaction product. 7

5. The process of producing a condensation product which includesrefluxing a mixture com- 6. The process of producing a condensationproduct which includes refluxing a mixture com prising Raney alloy,water, butyl 4-(chloromethyDbenzoate and recoveringl,2-bis(4,4"-carbobutoxyphenyhethane from the reaction product.

7. The process of producing a condensation product which includesrefluxing a mixture comprising Raney alloy, water and Z-ethylhexylROBERT A. HEIMSCH.

WILLIAM S. EMERSON.

REFERENCES CITED The following references are of record in the fileofthis patent:

.Sabatier, Catalysis in Organic Chemistry ,(sec- 0nd printing), page148, paragraph 402 (1923 edition).

Adkins, Reactions of Hydrogen, edition).

pp. 19-20. (19ml

1. A PROCESS FOR PRODUCING A DICARBOXYLATE HAVING THE GENERAL STRUCTURE: